Physical & Chemical Changes

at the particulate level

E. Mylar BalloonPhysical or Chemical Change?Physical or Chemical Change?

A.Fog in a Bottledust particle

water molecule

Physical or Chemical Change?Physical or Chemical Change?

H2O (g)

H2O (l)

B. Dropper Bottles

KI

Pb(NO3)2

2 KI (aq) + Pb(NO3)2 (aq)

2 KNO3 (aq) + PbI2 (s)

Physical or Chemical Change?Physical or Chemical Change?

C. Iodine

I2 (s)

I2 (g)

I2 (s)

Physical or Chemical Change?Physical or Chemical Change?

The PHASE changes s l l s l g g l s g g s

The PHASE changes s l l s l g g l s g g s

meltfreezeboilcondensesublimedeposit

D. Alka-SeltzerPhysical or Chemical Change?Physical or Chemical Change?

water molecule

NaHCO3 CO2

fizzing = effervescence

F. Talking with SF6

N2= 2 x ~14 amu = 28 amu

O2= 2 x ~16 amu = 32 amu

SF6= 32 amu+[6 x ~19 amu] = ~146 amu

He= ~4 amuHe

N2

O2

SF6

air

Particles with less mass vibrate faster across the vocal cords.Particles with more mass vibrate more slowly across the vocal cords.

Physical or Chemical Change?Physical or Chemical Change?